xref: /freebsd/sys/geom/label/g_label.c (revision 0572ccaa4543b0abef8ef81e384c1d04de9f3da1)
1 /*-
2  * Copyright (c) 2004-2005 Pawel Jakub Dawidek <pjd@FreeBSD.org>
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include "opt_geom.h"
31 
32 #include <sys/param.h>
33 #include <sys/systm.h>
34 #include <sys/kernel.h>
35 #include <sys/module.h>
36 #include <sys/lock.h>
37 #include <sys/mutex.h>
38 #include <sys/bio.h>
39 #include <sys/ctype.h>
40 #include <sys/malloc.h>
41 #include <sys/libkern.h>
42 #include <sys/sbuf.h>
43 #include <sys/sysctl.h>
44 #include <geom/geom.h>
45 #include <geom/geom_slice.h>
46 #include <geom/label/g_label.h>
47 
48 FEATURE(geom_label, "GEOM labeling support");
49 
50 SYSCTL_DECL(_kern_geom);
51 SYSCTL_NODE(_kern_geom, OID_AUTO, label, CTLFLAG_RW, 0, "GEOM_LABEL stuff");
52 u_int g_label_debug = 0;
53 TUNABLE_INT("kern.geom.label.debug", &g_label_debug);
54 SYSCTL_UINT(_kern_geom_label, OID_AUTO, debug, CTLFLAG_RW, &g_label_debug, 0,
55     "Debug level");
56 
57 static int g_label_destroy_geom(struct gctl_req *req, struct g_class *mp,
58     struct g_geom *gp);
59 static int g_label_destroy(struct g_geom *gp, boolean_t force);
60 static struct g_geom *g_label_taste(struct g_class *mp, struct g_provider *pp,
61     int flags __unused);
62 static void g_label_config(struct gctl_req *req, struct g_class *mp,
63     const char *verb);
64 
65 struct g_class g_label_class = {
66 	.name = G_LABEL_CLASS_NAME,
67 	.version = G_VERSION,
68 	.ctlreq = g_label_config,
69 	.taste = g_label_taste,
70 	.destroy_geom = g_label_destroy_geom
71 };
72 
73 /*
74  * To add a new file system where you want to look for volume labels,
75  * you have to:
76  * 1. Add a file g_label_<file system>.c which implements labels recognition.
77  * 2. Add an 'extern const struct g_label_desc g_label_<file system>;' into
78  *    g_label.h file.
79  * 3. Add an element to the table below '&g_label_<file system>,'.
80  * 4. Add your file to sys/conf/files.
81  * 5. Add your file to sys/modules/geom/geom_label/Makefile.
82  * 6. Add your file system to manual page sbin/geom/class/label/glabel.8.
83  */
84 const struct g_label_desc *g_labels[] = {
85 	&g_label_gpt,
86 	&g_label_gpt_uuid,
87 #ifdef GEOM_LABEL
88 	&g_label_ufs_id,
89 	&g_label_ufs_volume,
90 	&g_label_iso9660,
91 	&g_label_msdosfs,
92 	&g_label_ext2fs,
93 	&g_label_reiserfs,
94 	&g_label_ntfs,
95 	&g_label_disk_ident,
96 #endif
97 	NULL
98 };
99 
100 
101 static int
102 g_label_destroy_geom(struct gctl_req *req __unused, struct g_class *mp,
103     struct g_geom *gp __unused)
104 {
105 
106 	/*
107 	 * XXX: Unloading a class which is using geom_slice:1.56 is currently
108 	 * XXX: broken, so we deny unloading when we have geoms.
109 	 */
110 	return (EOPNOTSUPP);
111 }
112 
113 static void
114 g_label_orphan(struct g_consumer *cp)
115 {
116 
117 	G_LABEL_DEBUG(1, "Label %s removed.",
118 	    LIST_FIRST(&cp->geom->provider)->name);
119 	g_slice_orphan(cp);
120 }
121 
122 static void
123 g_label_spoiled(struct g_consumer *cp)
124 {
125 
126 	G_LABEL_DEBUG(1, "Label %s removed.",
127 	    LIST_FIRST(&cp->geom->provider)->name);
128 	g_slice_spoiled(cp);
129 }
130 
131 static void
132 g_label_resize(struct g_consumer *cp)
133 {
134 
135 	G_LABEL_DEBUG(1, "Label %s resized.",
136 	    LIST_FIRST(&cp->geom->provider)->name);
137 
138 	g_slice_config(cp->geom, 0, G_SLICE_CONFIG_FORCE, (off_t)0,
139 	    cp->provider->mediasize, cp->provider->sectorsize, "notused");
140 }
141 
142 static int
143 g_label_is_name_ok(const char *label)
144 {
145 	const char *s;
146 
147 	/* Check if the label starts from ../ */
148 	if (strncmp(label, "../", 3) == 0)
149 		return (0);
150 	/* Check if the label contains /../ */
151 	if (strstr(label, "/../") != NULL)
152 		return (0);
153 	/* Check if the label ends at ../ */
154 	if ((s = strstr(label, "/..")) != NULL && s[3] == '\0')
155 		return (0);
156 	return (1);
157 }
158 
159 static void
160 g_label_mangle_name(char *label, size_t size)
161 {
162 	struct sbuf *sb;
163 	const u_char *c;
164 
165 	sb = sbuf_new(NULL, NULL, size, SBUF_FIXEDLEN);
166 	for (c = label; *c != '\0'; c++) {
167 		if (!isprint(*c) || isspace(*c) || *c =='"' || *c == '%')
168 			sbuf_printf(sb, "%%%02X", *c);
169 		else
170 			sbuf_putc(sb, *c);
171 	}
172 	if (sbuf_finish(sb) != 0)
173 		label[0] = '\0';
174 	else
175 		strlcpy(label, sbuf_data(sb), size);
176 	sbuf_delete(sb);
177 }
178 
179 static struct g_geom *
180 g_label_create(struct gctl_req *req, struct g_class *mp, struct g_provider *pp,
181     const char *label, const char *dir, off_t mediasize)
182 {
183 	struct g_geom *gp;
184 	struct g_provider *pp2;
185 	struct g_consumer *cp;
186 	char name[64];
187 
188 	g_topology_assert();
189 
190 	if (!g_label_is_name_ok(label)) {
191 		G_LABEL_DEBUG(0, "%s contains suspicious label, skipping.",
192 		    pp->name);
193 		G_LABEL_DEBUG(1, "%s suspicious label is: %s", pp->name, label);
194 		if (req != NULL)
195 			gctl_error(req, "Label name %s is invalid.", label);
196 		return (NULL);
197 	}
198 	gp = NULL;
199 	cp = NULL;
200 	snprintf(name, sizeof(name), "%s/%s", dir, label);
201 	LIST_FOREACH(gp, &mp->geom, geom) {
202 		pp2 = LIST_FIRST(&gp->provider);
203 		if (pp2 == NULL)
204 			continue;
205 		if ((pp2->flags & G_PF_ORPHAN) != 0)
206 			continue;
207 		if (strcmp(pp2->name, name) == 0) {
208 			G_LABEL_DEBUG(1, "Label %s(%s) already exists (%s).",
209 			    label, name, pp->name);
210 			if (req != NULL) {
211 				gctl_error(req, "Provider %s already exists.",
212 				    name);
213 			}
214 			return (NULL);
215 		}
216 	}
217 	gp = g_slice_new(mp, 1, pp, &cp, NULL, 0, NULL);
218 	if (gp == NULL) {
219 		G_LABEL_DEBUG(0, "Cannot create slice %s.", label);
220 		if (req != NULL)
221 			gctl_error(req, "Cannot create slice %s.", label);
222 		return (NULL);
223 	}
224 	gp->orphan = g_label_orphan;
225 	gp->spoiled = g_label_spoiled;
226 	gp->resize = g_label_resize;
227 	g_access(cp, -1, 0, 0);
228 	g_slice_config(gp, 0, G_SLICE_CONFIG_SET, (off_t)0, mediasize,
229 	    pp->sectorsize, "%s", name);
230 	G_LABEL_DEBUG(1, "Label for provider %s is %s.", pp->name, name);
231 	return (gp);
232 }
233 
234 static int
235 g_label_destroy(struct g_geom *gp, boolean_t force)
236 {
237 	struct g_provider *pp;
238 
239 	g_topology_assert();
240 	pp = LIST_FIRST(&gp->provider);
241 	if (pp != NULL && (pp->acr != 0 || pp->acw != 0 || pp->ace != 0)) {
242 		if (force) {
243 			G_LABEL_DEBUG(0, "Provider %s is still open, so it "
244 			    "can't be definitely removed.", pp->name);
245 		} else {
246 			G_LABEL_DEBUG(1,
247 			    "Provider %s is still open (r%dw%de%d).", pp->name,
248 			    pp->acr, pp->acw, pp->ace);
249 			return (EBUSY);
250 		}
251 	} else if (pp != NULL)
252 		G_LABEL_DEBUG(1, "Label %s removed.", pp->name);
253 	g_slice_spoiled(LIST_FIRST(&gp->consumer));
254 	return (0);
255 }
256 
257 static int
258 g_label_read_metadata(struct g_consumer *cp, struct g_label_metadata *md)
259 {
260 	struct g_provider *pp;
261 	u_char *buf;
262 	int error;
263 
264 	g_topology_assert();
265 
266 	pp = cp->provider;
267 	g_topology_unlock();
268 	buf = g_read_data(cp, pp->mediasize - pp->sectorsize, pp->sectorsize,
269 	    &error);
270 	g_topology_lock();
271 	if (buf == NULL)
272 		return (error);
273 	/* Decode metadata. */
274 	label_metadata_decode(buf, md);
275 	g_free(buf);
276 
277 	return (0);
278 }
279 
280 static void
281 g_label_orphan_taste(struct g_consumer *cp __unused)
282 {
283 
284 	KASSERT(1 == 0, ("%s called?", __func__));
285 }
286 
287 static void
288 g_label_start_taste(struct bio *bp __unused)
289 {
290 
291 	KASSERT(1 == 0, ("%s called?", __func__));
292 }
293 
294 static int
295 g_label_access_taste(struct g_provider *pp __unused, int dr __unused,
296     int dw __unused, int de __unused)
297 {
298 
299 	KASSERT(1 == 0, ("%s called", __func__));
300 	return (EOPNOTSUPP);
301 }
302 
303 static struct g_geom *
304 g_label_taste(struct g_class *mp, struct g_provider *pp, int flags __unused)
305 {
306 	struct g_label_metadata md;
307 	struct g_consumer *cp;
308 	struct g_geom *gp;
309 	int i;
310 
311 	g_trace(G_T_TOPOLOGY, "%s(%s, %s)", __func__, mp->name, pp->name);
312 	g_topology_assert();
313 
314 	G_LABEL_DEBUG(2, "Tasting %s.", pp->name);
315 
316 	/* Skip providers that are already open for writing. */
317 	if (pp->acw > 0)
318 		return (NULL);
319 
320 	if (strcmp(pp->geom->class->name, mp->name) == 0)
321 		return (NULL);
322 
323 	gp = g_new_geomf(mp, "label:taste");
324 	gp->start = g_label_start_taste;
325 	gp->access = g_label_access_taste;
326 	gp->orphan = g_label_orphan_taste;
327 	cp = g_new_consumer(gp);
328 	g_attach(cp, pp);
329 	if (g_access(cp, 1, 0, 0) != 0)
330 		goto end;
331 	do {
332 		if (g_label_read_metadata(cp, &md) != 0)
333 			break;
334 		if (strcmp(md.md_magic, G_LABEL_MAGIC) != 0)
335 			break;
336 		if (md.md_version > G_LABEL_VERSION) {
337 			printf("geom_label.ko module is too old to handle %s.\n",
338 			    pp->name);
339 			break;
340 		}
341 
342 		/*
343 		 * Backward compatibility:
344 		 */
345 		/*
346 		 * There was no md_provsize field in earlier versions of
347 		 * metadata.
348 		 */
349 		if (md.md_version < 2)
350 			md.md_provsize = pp->mediasize;
351 
352 		if (md.md_provsize != pp->mediasize)
353 			break;
354 
355 		g_label_create(NULL, mp, pp, md.md_label, G_LABEL_DIR,
356 		    pp->mediasize - pp->sectorsize);
357 	} while (0);
358 	for (i = 0; g_labels[i] != NULL; i++) {
359 		char label[128];
360 
361 		if (g_labels[i]->ld_enabled == 0)
362 			continue;
363 		g_topology_unlock();
364 		g_labels[i]->ld_taste(cp, label, sizeof(label));
365 		g_label_mangle_name(label, sizeof(label));
366 		g_topology_lock();
367 		if (label[0] == '\0')
368 			continue;
369 		g_label_create(NULL, mp, pp, label, g_labels[i]->ld_dir,
370 		    pp->mediasize);
371 	}
372 	g_access(cp, -1, 0, 0);
373 end:
374 	g_detach(cp);
375 	g_destroy_consumer(cp);
376 	g_destroy_geom(gp);
377 	return (NULL);
378 }
379 
380 static void
381 g_label_ctl_create(struct gctl_req *req, struct g_class *mp)
382 {
383 	struct g_provider *pp;
384 	const char *name;
385 	int *nargs;
386 
387 	g_topology_assert();
388 
389 	nargs = gctl_get_paraml(req, "nargs", sizeof(*nargs));
390 	if (nargs == NULL) {
391 		gctl_error(req, "No '%s' argument", "nargs");
392 		return;
393 	}
394 	if (*nargs != 2) {
395 		gctl_error(req, "Invalid number of arguments.");
396 		return;
397 	}
398 	/*
399 	 * arg1 is the name of provider.
400 	 */
401 	name = gctl_get_asciiparam(req, "arg1");
402 	if (name == NULL) {
403 		gctl_error(req, "No 'arg%d' argument", 1);
404 		return;
405 	}
406 	if (strncmp(name, "/dev/", strlen("/dev/")) == 0)
407 		name += strlen("/dev/");
408 	pp = g_provider_by_name(name);
409 	if (pp == NULL) {
410 		G_LABEL_DEBUG(1, "Provider %s is invalid.", name);
411 		gctl_error(req, "Provider %s is invalid.", name);
412 		return;
413 	}
414 	/*
415 	 * arg0 is the label.
416 	 */
417 	name = gctl_get_asciiparam(req, "arg0");
418 	if (name == NULL) {
419 		gctl_error(req, "No 'arg%d' argument", 0);
420 		return;
421 	}
422 	g_label_create(req, mp, pp, name, G_LABEL_DIR, pp->mediasize);
423 }
424 
425 static const char *
426 g_label_skip_dir(const char *name)
427 {
428 	char path[64];
429 	u_int i;
430 
431 	if (strncmp(name, "/dev/", strlen("/dev/")) == 0)
432 		name += strlen("/dev/");
433 	if (strncmp(name, G_LABEL_DIR "/", strlen(G_LABEL_DIR "/")) == 0)
434 		name += strlen(G_LABEL_DIR "/");
435 	for (i = 0; g_labels[i] != NULL; i++) {
436 		snprintf(path, sizeof(path), "%s/", g_labels[i]->ld_dir);
437 		if (strncmp(name, path, strlen(path)) == 0) {
438 			name += strlen(path);
439 			break;
440 		}
441 	}
442 	return (name);
443 }
444 
445 static struct g_geom *
446 g_label_find_geom(struct g_class *mp, const char *name)
447 {
448 	struct g_geom *gp;
449 	struct g_provider *pp;
450 	const char *pname;
451 
452 	name = g_label_skip_dir(name);
453 	LIST_FOREACH(gp, &mp->geom, geom) {
454 		pp = LIST_FIRST(&gp->provider);
455 		pname = g_label_skip_dir(pp->name);
456 		if (strcmp(pname, name) == 0)
457 			return (gp);
458 	}
459 	return (NULL);
460 }
461 
462 static void
463 g_label_ctl_destroy(struct gctl_req *req, struct g_class *mp)
464 {
465 	int *nargs, *force, error, i;
466 	struct g_geom *gp;
467 	const char *name;
468 	char param[16];
469 
470 	g_topology_assert();
471 
472 	nargs = gctl_get_paraml(req, "nargs", sizeof(*nargs));
473 	if (nargs == NULL) {
474 		gctl_error(req, "No '%s' argument", "nargs");
475 		return;
476 	}
477 	if (*nargs <= 0) {
478 		gctl_error(req, "Missing device(s).");
479 		return;
480 	}
481 	force = gctl_get_paraml(req, "force", sizeof(*force));
482 	if (force == NULL) {
483 		gctl_error(req, "No 'force' argument");
484 		return;
485 	}
486 
487 	for (i = 0; i < *nargs; i++) {
488 		snprintf(param, sizeof(param), "arg%d", i);
489 		name = gctl_get_asciiparam(req, param);
490 		if (name == NULL) {
491 			gctl_error(req, "No 'arg%d' argument", i);
492 			return;
493 		}
494 		gp = g_label_find_geom(mp, name);
495 		if (gp == NULL) {
496 			G_LABEL_DEBUG(1, "Label %s is invalid.", name);
497 			gctl_error(req, "Label %s is invalid.", name);
498 			return;
499 		}
500 		error = g_label_destroy(gp, *force);
501 		if (error != 0) {
502 			gctl_error(req, "Cannot destroy label %s (error=%d).",
503 			    LIST_FIRST(&gp->provider)->name, error);
504 			return;
505 		}
506 	}
507 }
508 
509 static void
510 g_label_config(struct gctl_req *req, struct g_class *mp, const char *verb)
511 {
512 	uint32_t *version;
513 
514 	g_topology_assert();
515 
516 	version = gctl_get_paraml(req, "version", sizeof(*version));
517 	if (version == NULL) {
518 		gctl_error(req, "No '%s' argument.", "version");
519 		return;
520 	}
521 	if (*version != G_LABEL_VERSION) {
522 		gctl_error(req, "Userland and kernel parts are out of sync.");
523 		return;
524 	}
525 
526 	if (strcmp(verb, "create") == 0) {
527 		g_label_ctl_create(req, mp);
528 		return;
529 	} else if (strcmp(verb, "destroy") == 0 ||
530 	    strcmp(verb, "stop") == 0) {
531 		g_label_ctl_destroy(req, mp);
532 		return;
533 	}
534 
535 	gctl_error(req, "Unknown verb.");
536 }
537 
538 DECLARE_GEOM_CLASS(g_label_class, g_label);
539